using System;

public class Program

{

    private delegate void t_somefunc (int a, int b);

    private static t_somefunc callbacks;

    public static void Main()

    {

        callbacks += (a,b)=>Console.WriteLine(a+b);

        callbacks += (a,b)=>Console.WriteLine(a*b);

        callbacks += (a,b)=>Console.WriteLine(a-b);

        callbacks(5,2);

    }

}